1. class Super {
2. public float getNum() { return 3.0f; }
3. }
4.
5. public class Sub extends Super {
6.
7. }
Which method, placed at line6, causes compilation to fail?()
A. public void getNum(){}
B. public void getNum(double d){}
C. public float getNum() { return 4.0f; }
D. public double getNum(float d) { return 4.0d; }
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public class Test {
public int aMethod() {
static int i = 0;
i++;
return i;
}
public static void main (String args[]) {
Test test = new Test();
test.aMethod();
int j = test.aMethod();
System.out.println(j);
}
}
What is the result?()
A. 0
B. 1
C. 2
D. Compilation fails.
public class ArrayTest {
public static void main(String[] args) {
float fl[], f2[];
fl = new float[10];
f2 = f1;
System.out.println(“f2[0]= “ + f2[0]);
}
}
What is the result?()
A. It prints f2[0] = 0.0.
B. It prints f2[0] = NaN.
C. An error at line 5 causes compile to fail.
D. An error at line 6 causes compile to fail.
E. An error at line 6 causes an expectation at runtime.
public class Test{
public static void main( String[] argv ){
// insert statement here
}
}
Which statement, inserted at line 3, produces the following output?()
Exception in thread “main” java.lang.AssertionError: true at Test.main(Test.java:3)
A. assert true;
B. assert false;
C. assert false : true;
D. assert false == true;
E. assert false: false;
public class Delta {
static boolean foo(char c) {
System.out.print(c);
return true;
}
public static void main( String[] argv ) {
int i =0;
for ( foo(‘A’); foo(‘B’)&&(i<2); foo(‘C’)){
i++ ;
foo(‘D’);
}
}
}
What is the result?()
A. ABDCBDCB
B. ABCDABCD
C. Compilation fails.
D. An exception is thrown at runtime.
class A {
protected int method1(int a, int b) { return 0; }
}
Which two are valid in a class that extends class A?()
A. public int method1(int a, int b) { return 0; }
B. private int method1(int a, int b) { return 0; }
C. private int method1(int a, long b) { return 0; }
D. public short method1(int a, int b) { return 0: }
E. static protected int method1(int a, int b) { return 0; }
package test1;
public class Test1 {
static int x = 42;
}
package test2;
public class Test2 extends test1.Test1 {
public static void main(String[] args) {
System.out.println(“x = “ + x);
}
}
What is the result?()
A. x = 0
B. x = 42
C. Compilation fails because of an error in line 2 of class Test2.
D. Compilation fails because of an error in line 3 of class Test1.
E. Compilation fails because of an error in line 4 of class Test2.
public interface Foo {
int k = 4; 3. }
Which three are equivalent to line 2?()
A. final int k = 4;
B. public int k = 4;
C. static int k = 4;
D. abstract int k = 4;
E. volatile int k = 4;
F. protected int k = 4;
public class Test {
public static void aMethod() throws Exception {
try {
throw new Exception();
} finally {
System.out.println(“finally”);
}
}
public static void main(String args[]) {
try {
aMethod();
} catch (Exception e) {
System.out.println(“exception”);
}
System.out.println(“finished”);
}
}
What is the result?()
A. finally
B. exception finished
C. finally exception finished
D. Compilation fails.
int x = 3;
int y = 1;
if (x = y) {
System.out.println(“x = “ + x);
}
What is the result? ()
A.x=1
B.x=3
C.Compilation&ensp;fails.
D.The&ensp;code&ensp;runs&ensp;with&ensp;no&ensp;output.&ensp;
E.An&ensp;exception&ensp;is&ensp;thrown&ensp;at&ensp;runtime.
A. public
B. private
C. protected
D. transient
E. default access
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